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2026-04-02erofs: add GFP_NOIO in the bio completion if neededJiucheng Xu1-0/+3
commit c23df30915f83e7257c8625b690a1cece94142a0 upstream. The bio completion path in the process context (e.g. dm-verity) will directly call into decompression rather than trigger another workqueue context for minimal scheduling latencies, which can then call vm_map_ram() with GFP_KERNEL. Due to insufficient memory, vm_map_ram() may generate memory swapping I/O, which can cause submit_bio_wait to deadlock in some scenarios. Trimmed down the call stack, as follows: f2fs_submit_read_io submit_bio //bio_list is initialized. mmc_blk_mq_recovery z_erofs_endio vm_map_ram __pte_alloc_kernel __alloc_pages_direct_reclaim shrink_folio_list __swap_writepage submit_bio_wait //bio_list is non-NULL, hang!!! Use memalloc_noio_{save,restore}() to wrap up this path. Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Jiucheng Xu <jiucheng.xu@amlogic.com> Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-02erofs: set fileio bio failed in short read caseSheng Yong1-4/+2
[ Upstream commit eade54040384f54b7fb330e4b0975c5734850b3c ] For file-backed mount, IO requests are handled by vfs_iocb_iter_read(). However, it can be interrupted by SIGKILL, returning the number of bytes actually copied. Unused folios in bio are unexpectedly marked as uptodate. vfs_read filemap_read filemap_get_pages filemap_readahead erofs_fileio_readahead erofs_fileio_rq_submit vfs_iocb_iter_read filemap_read filemap_get_pages <= detect signal erofs_fileio_ki_complete <= set all folios uptodate This patch addresses this by setting short read bio with an error directly. Fixes: bc804a8d7e86 ("erofs: handle end of filesystem properly for file-backed mounts") Reported-by: chenguanyou <chenguanyou@xiaomi.com> Signed-off-by: Yunlei He <heyunlei@xiaomi.com> Signed-off-by: Sheng Yong <shengyong1@xiaomi.com> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-03-25erofs: fix inline data read failure for ztailpacking pclustersGao Xiang1-10/+11
[ Upstream commit c134a40f86efb8d6b5a949ef70e06d5752209be5 ] Compressed folios for ztailpacking pclusters must be valid before adding these pclusters to I/O chains. Otherwise, z_erofs_decompress_pcluster() may assume they are already valid and then trigger a NULL pointer dereference. It is somewhat hard to reproduce because the inline data is in the same block as the tail of the compressed indexes, which are usually read just before. However, it may still happen if a fatal signal arrives while read_mapping_folio() is running, as shown below: erofs: (device dm-1): z_erofs_pcluster_begin: failed to get inline data -4 Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008 ... pc : z_erofs_decompress_queue+0x4c8/0xa14 lr : z_erofs_decompress_queue+0x160/0xa14 sp : ffffffc08b3eb3a0 x29: ffffffc08b3eb570 x28: ffffffc08b3eb418 x27: 0000000000001000 x26: ffffff8086ebdbb8 x25: ffffff8086ebdbb8 x24: 0000000000000001 x23: 0000000000000008 x22: 00000000fffffffb x21: dead000000000700 x20: 00000000000015e7 x19: ffffff808babb400 x18: ffffffc089edc098 x17: 00000000c006287d x16: 00000000c006287d x15: 0000000000000004 x14: ffffff80ba8f8000 x13: 0000000000000004 x12: 00000006589a77c9 x11: 0000000000000015 x10: 0000000000000000 x9 : 0000000000000000 x8 : 0000000000000000 x7 : 0000000000000000 x6 : 000000000000003f x5 : 0000000000000040 x4 : ffffffffffffffe0 x3 : 0000000000000020 x2 : 0000000000000008 x1 : 0000000000000000 x0 : 0000000000000000 Call trace: z_erofs_decompress_queue+0x4c8/0xa14 z_erofs_runqueue+0x908/0x97c z_erofs_read_folio+0x128/0x228 filemap_read_folio+0x68/0x128 filemap_get_pages+0x44c/0x8b4 filemap_read+0x12c/0x5b8 generic_file_read_iter+0x4c/0x15c do_iter_readv_writev+0x188/0x1e0 vfs_iter_read+0xac/0x1a4 backing_file_read_iter+0x170/0x34c ovl_read_iter+0xf0/0x140 vfs_read+0x28c/0x344 ksys_read+0x80/0xf0 __arm64_sys_read+0x24/0x34 invoke_syscall+0x60/0x114 el0_svc_common+0x88/0xe4 do_el0_svc+0x24/0x30 el0_svc+0x40/0xa8 el0t_64_sync_handler+0x70/0xbc el0t_64_sync+0x1bc/0x1c0 Fix this by reading the inline data before allocating and adding the pclusters to the I/O chains. Fixes: cecf864d3d76 ("erofs: support inline data decompression") Reported-by: Zhiguo Niu <zhiguo.niu@unisoc.com> Reviewed-and-tested-by: Zhiguo Niu <zhiguo.niu@unisoc.com> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-03-04erofs: handle end of filesystem properly for file-backed mountsGao Xiang1-12/+8
[ Upstream commit bc804a8d7e865ef47fb7edcaf5e77d18bf444ebc ] I/O requests beyond the end of the filesystem should be zeroed out, similar to loopback devices and that is what we expect. Fixes: ce63cb62d794 ("erofs: support unencoded inodes for fileio") Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-03-04erofs: get rid of raw bi_end_io() usageGao Xiang2-3/+3
[ Upstream commit 80d0c27a0a4af8e0678d7412781482e6f73c22c7 ] These BIOs are actually harmless in practice, as they are all pseudo BIOs and do not use advanced features like chaining. Using the BIO interface is a more friendly and unified approach for both bdev and and file-backed I/Os (compared to awkward bvec interfaces). Let's use bio_endio() instead. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Stable-dep-of: bc804a8d7e86 ("erofs: handle end of filesystem properly for file-backed mounts") Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-16erofs: fix UAF issue for file-backed mounts w/ directio optionChao Yu1-1/+6
commit 1caf50ce4af096d0280d59a31abdd85703cd995c upstream. [ 9.269940][ T3222] Call trace: [ 9.269948][ T3222] ext4_file_read_iter+0xac/0x108 [ 9.269979][ T3222] vfs_iocb_iter_read+0xac/0x198 [ 9.269993][ T3222] erofs_fileio_rq_submit+0x12c/0x180 [ 9.270008][ T3222] erofs_fileio_submit_bio+0x14/0x24 [ 9.270030][ T3222] z_erofs_runqueue+0x834/0x8ac [ 9.270054][ T3222] z_erofs_read_folio+0x120/0x220 [ 9.270083][ T3222] filemap_read_folio+0x60/0x120 [ 9.270102][ T3222] filemap_fault+0xcac/0x1060 [ 9.270119][ T3222] do_pte_missing+0x2d8/0x1554 [ 9.270131][ T3222] handle_mm_fault+0x5ec/0x70c [ 9.270142][ T3222] do_page_fault+0x178/0x88c [ 9.270167][ T3222] do_translation_fault+0x38/0x54 [ 9.270183][ T3222] do_mem_abort+0x54/0xac [ 9.270208][ T3222] el0_da+0x44/0x7c [ 9.270227][ T3222] el0t_64_sync_handler+0x5c/0xf4 [ 9.270253][ T3222] el0t_64_sync+0x1bc/0x1c0 EROFS may encounter above panic when enabling file-backed mount w/ directio mount option, the root cause is it may suffer UAF in below race condition: - z_erofs_read_folio wq s_dio_done_wq - z_erofs_runqueue - erofs_fileio_submit_bio - erofs_fileio_rq_submit - vfs_iocb_iter_read - ext4_file_read_iter - ext4_dio_read_iter - iomap_dio_rw : bio was submitted and return -EIOCBQUEUED - dio_aio_complete_work - dio_complete - dio->iocb->ki_complete (erofs_fileio_ki_complete()) - kfree(rq) : it frees iocb, iocb.ki_filp can be UAF in file_accessed(). - file_accessed : access NULL file point Introduce a reference count in struct erofs_fileio_rq, and initialize it as two, both erofs_fileio_ki_complete() and erofs_fileio_rq_submit() will decrease reference count, the last one decreasing the reference count to zero will free rq. Cc: stable@kernel.org Fixes: fb176750266a ("erofs: add file-backed mount support") Fixes: 6422cde1b0d5 ("erofs: use buffered I/O for file-backed mounts by default") Signed-off-by: Chao Yu <chao@kernel.org> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-17erofs: fix file-backed mounts no longer working on EROFS partitionsGao Xiang1-1/+2
[ Upstream commit 7893cc12251f6f19e7689a4cf3ba803bddbd8437 ] Sheng Yong reported [1] that Android APEX images didn't work with commit 072a7c7cdbea ("erofs: don't bother with s_stack_depth increasing for now") because "EROFS-formatted APEX file images can be stored within an EROFS-formatted Android system partition." In response, I sent a quick fat-fingered [PATCH v3] to address the report. Unfortunately, the updated condition was incorrect: if (erofs_is_fileio_mode(sbi)) { - sb->s_stack_depth = - file_inode(sbi->dif0.file)->i_sb->s_stack_depth + 1; - if (sb->s_stack_depth > FILESYSTEM_MAX_STACK_DEPTH) { - erofs_err(sb, "maximum fs stacking depth exceeded"); + inode = file_inode(sbi->dif0.file); + if ((inode->i_sb->s_op == &erofs_sops && !sb->s_bdev) || + inode->i_sb->s_stack_depth) { The condition `!sb->s_bdev` is always true for all file-backed EROFS mounts, making the check effectively a no-op. The real fix tested and confirmed by Sheng Yong [2] at that time was [PATCH v3 RESEND], which correctly ensures the following EROFS^2 setup works: EROFS (on a block device) + EROFS (file-backed mount) But sadly I screwed it up again by upstreaming the outdated [PATCH v3]. This patch applies the same logic as the delta between the upstream [PATCH v3] and the real fix [PATCH v3 RESEND]. Reported-by: Sheng Yong <shengyong1@xiaomi.com> Closes: https://lore.kernel.org/r/3acec686-4020-4609-aee4-5dae7b9b0093@gmail.com [1] Fixes: 072a7c7cdbea ("erofs: don't bother with s_stack_depth increasing for now") Link: https://lore.kernel.org/r/243f57b8-246f-47e7-9fb1-27a771e8e9e8@gmail.com [2] Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17erofs: don't bother with s_stack_depth increasing for nowGao Xiang1-6/+12
[ Upstream commit 072a7c7cdbea4f91df854ee2bb216256cd619f2a ] Previously, commit d53cd891f0e4 ("erofs: limit the level of fs stacking for file-backed mounts") bumped `s_stack_depth` by one to avoid kernel stack overflow when stacking an unlimited number of EROFS on top of each other. This fix breaks composefs mounts, which need EROFS+ovl^2 sometimes (and such setups are already used in production for quite a long time). One way to fix this regression is to bump FILESYSTEM_MAX_STACK_DEPTH from 2 to 3, but proving that this is safe in general is a high bar. After a long discussion on GitHub issues [1] about possible solutions, one conclusion is that there is no need to support nesting file-backed EROFS mounts on stacked filesystems, because there is always the option to use loopback devices as a fallback. As a quick fix for the composefs regression for this cycle, instead of bumping `s_stack_depth` for file backed EROFS mounts, we disallow nesting file-backed EROFS over EROFS and over filesystems with `s_stack_depth` > 0. This works for all known file-backed mount use cases (composefs, containerd, and Android APEX for some Android vendors), and the fix is self-contained. Essentially, we are allowing one extra unaccounted fs stacking level of EROFS below stacking filesystems, but EROFS can only be used in the read path (i.e. overlayfs lower layers), which typically has much lower stack usage than the write path. We can consider increasing FILESYSTEM_MAX_STACK_DEPTH later, after more stack usage analysis or using alternative approaches, such as splitting the `s_stack_depth` limitation according to different combinations of stacking. Fixes: d53cd891f0e4 ("erofs: limit the level of fs stacking for file-backed mounts") Reported-and-tested-by: Dusty Mabe <dusty@dustymabe.com> Reported-by: Timothée Ravier <tim@siosm.fr> Closes: https://github.com/coreos/fedora-coreos-tracker/issues/2087 [1] Reported-by: "Alekséi Naidénov" <an@digitaltide.io> Closes: https://lore.kernel.org/r/CAFHtUiYv4+=+JP_-JjARWjo6OwcvBj1wtYN=z0QXwCpec9sXtg@mail.gmail.com Acked-by: Amir Goldstein <amir73il@gmail.com> Acked-by: Alexander Larsson <alexl@redhat.com> Reviewed-and-tested-by: Sheng Yong <shengyong1@xiaomi.com> Reviewed-by: Zhiguo Niu <zhiguo.niu@unisoc.com> Reviewed-by: Chao Yu <chao@kernel.org> Cc: Christian Brauner <brauner@kernel.org> Cc: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-08erofs: fix unexpected EIO under memory pressureJunbeom Yeom1-4/+4
[ Upstream commit 4012d78562193ef5eb613bad4b0c0fa187637cfe ] erofs readahead could fail with ENOMEM under the memory pressure because it tries to alloc_page with GFP_NOWAIT | GFP_NORETRY, while GFP_KERNEL for a regular read. And if readahead fails (with non-uptodate folios), the original request will then fall back to synchronous read, and `.read_folio()` should return appropriate errnos. However, in scenarios where readahead and read operations compete, read operation could return an unintended EIO because of an incorrect error propagation. To resolve this, this patch modifies the behavior so that, when the PCL is for read(which means pcl.besteffort is true), it attempts actual decompression instead of propagating the privios error except initial EIO. - Page size: 4K - The original size of FileA: 16K - Compress-ratio per PCL: 50% (Uncompressed 8K -> Compressed 4K) [page0, page1] [page2, page3] [PCL0]---------[PCL1] - functions declaration: . pread(fd, buf, count, offset) . readahead(fd, offset, count) - Thread A tries to read the last 4K - Thread B tries to do readahead 8K from 4K - RA, besteffort == false - R, besteffort == true <process A> <process B> pread(FileA, buf, 4K, 12K) do readahead(page3) // failed with ENOMEM wait_lock(page3) if (!uptodate(page3)) goto do_read readahead(FileA, 4K, 8K) // Here create PCL-chain like below: // [null, page1] [page2, null] // [PCL0:RA]-----[PCL1:RA] ... do read(page3) // found [PCL1:RA] and add page3 into it, // and then, change PCL1 from RA to R ... // Now, PCL-chain is as below: // [null, page1] [page2, page3] // [PCL0:RA]-----[PCL1:R] // try to decompress PCL-chain... z_erofs_decompress_queue err = 0; // failed with ENOMEM, so page 1 // only for RA will not be uptodated. // it's okay. err = decompress([PCL0:RA], err) // However, ENOMEM propagated to next // PCL, even though PCL is not only // for RA but also for R. As a result, // it just failed with ENOMEM without // trying any decompression, so page2 // and page3 will not be uptodated. ** BUG HERE ** --> err = decompress([PCL1:R], err) return err as ENOMEM ... wait_lock(page3) if (!uptodate(page3)) return EIO <-- Return an unexpected EIO! ... Fixes: 2349d2fa02db ("erofs: sunset unneeded NOFAILs") Cc: stable@vger.kernel.org Reviewed-by: Jaewook Kim <jw5454.kim@samsung.com> Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com> Signed-off-by: Junbeom Yeom <junbeom.yeom@samsung.com> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> [ Adjust context ] Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-12-18erofs: limit the level of fs stacking for file-backed mountsGao Xiang1-0/+16
[ Upstream commit d53cd891f0e4311889349fff3a784dc552f814b9 ] Otherwise, it could cause potential kernel stack overflow (e.g., EROFS mounting itself). Reviewed-by: Sheng Yong <shengyong1@xiaomi.com> Fixes: fb176750266a ("erofs: add file-backed mount support") Reviewed-by: Chao Yu <chao@kernel.org> Reviewed-by: Hongbo Li <lihongbo22@huawei.com> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-24erofs: avoid infinite loop due to incomplete zstd-compressed dataGao Xiang1-4/+7
[ Upstream commit f2a12cc3b97f062186568a7b94ddb7aa2ef68140 ] Currently, the decompression logic incorrectly spins if compressed data is truncated in crafted (deliberately corrupted) images. Fixes: 7c35de4df105 ("erofs: Zstandard compression support") Reported-by: Robert Morris <rtm@csail.mit.edu> Closes: https://lore.kernel.org/r/50958.1761605413@localhost Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Reviewed-by: Chunhai Guo <guochunhai@vivo.com> Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-09-04erofs: fix atomic context detection when !CONFIG_DEBUG_LOCK_ALLOCJunli Liu1-2/+11
[ Upstream commit c99fab6e80b76422741d34aafc2f930a482afbdd ] Since EROFS handles decompression in non-atomic contexts due to uncontrollable decompression latencies and vmap() usage, it tries to detect atomic contexts and only kicks off a kworker on demand in order to reduce unnecessary scheduling overhead. However, the current approach is insufficient and can lead to sleeping function calls in invalid contexts, causing kernel warnings and potential system instability. See the stacktrace [1] and previous discussion [2]. The current implementation only checks rcu_read_lock_any_held(), which behaves inconsistently across different kernel configurations: - When CONFIG_DEBUG_LOCK_ALLOC is enabled: correctly detects RCU critical sections by checking rcu_lock_map - When CONFIG_DEBUG_LOCK_ALLOC is disabled: compiles to "!preemptible()", which only checks preempt_count and misses RCU critical sections This patch introduces z_erofs_in_atomic() to provide comprehensive atomic context detection: 1. Check RCU preemption depth when CONFIG_PREEMPTION is enabled, as RCU critical sections may not affect preempt_count but still require atomic handling 2. Always use async processing when CONFIG_PREEMPT_COUNT is disabled, as preemption state cannot be reliably determined 3. Fall back to standard preemptible() check for remaining cases The function replaces the previous complex condition check and ensures that z_erofs always uses (kthread_)work in atomic contexts to minimize scheduling overhead and prevent sleeping in invalid contexts. [1] Problem stacktrace [ 61.266692] BUG: sleeping function called from invalid context at kernel/locking/rtmutex_api.c:510 [ 61.266702] in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 107, name: irq/54-ufshcd [ 61.266704] preempt_count: 0, expected: 0 [ 61.266705] RCU nest depth: 2, expected: 0 [ 61.266710] CPU: 0 UID: 0 PID: 107 Comm: irq/54-ufshcd Tainted: G W O 6.12.17 #1 [ 61.266714] Tainted: [W]=WARN, [O]=OOT_MODULE [ 61.266715] Hardware name: schumacher (DT) [ 61.266717] Call trace: [ 61.266718] dump_backtrace+0x9c/0x100 [ 61.266727] show_stack+0x20/0x38 [ 61.266728] dump_stack_lvl+0x78/0x90 [ 61.266734] dump_stack+0x18/0x28 [ 61.266736] __might_resched+0x11c/0x180 [ 61.266743] __might_sleep+0x64/0xc8 [ 61.266745] mutex_lock+0x2c/0xc0 [ 61.266748] z_erofs_decompress_queue+0xe8/0x978 [ 61.266753] z_erofs_decompress_kickoff+0xa8/0x190 [ 61.266756] z_erofs_endio+0x168/0x288 [ 61.266758] bio_endio+0x160/0x218 [ 61.266762] blk_update_request+0x244/0x458 [ 61.266766] scsi_end_request+0x38/0x278 [ 61.266770] scsi_io_completion+0x4c/0x600 [ 61.266772] scsi_finish_command+0xc8/0xe8 [ 61.266775] scsi_complete+0x88/0x148 [ 61.266777] blk_mq_complete_request+0x3c/0x58 [ 61.266780] scsi_done_internal+0xcc/0x158 [ 61.266782] scsi_done+0x1c/0x30 [ 61.266783] ufshcd_compl_one_cqe+0x12c/0x438 [ 61.266786] __ufshcd_transfer_req_compl+0x2c/0x78 [ 61.266788] ufshcd_poll+0xf4/0x210 [ 61.266789] ufshcd_transfer_req_compl+0x50/0x88 [ 61.266791] ufshcd_intr+0x21c/0x7c8 [ 61.266792] irq_forced_thread_fn+0x44/0xd8 [ 61.266796] irq_thread+0x1a4/0x358 [ 61.266799] kthread+0x12c/0x138 [ 61.266802] ret_from_fork+0x10/0x20 [2] https://lore.kernel.org/r/58b661d0-0ebb-4b45-a10d-c5927fb791cd@paulmck-laptop Signed-off-by: Junli Liu <liujunli@lixiang.com> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20250805011957.911186-1-liujunli@lixiang.com [ Gao Xiang: Use the original trace in v1. ] Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-01erofs: fix large fragment handlingGao Xiang3-6/+7
[ Upstream commit b44686c8391b427fb1c85a31c35077e6947c6d90 ] Fragments aren't limited by Z_EROFS_PCLUSTER_MAX_DSIZE. However, if a fragment's logical length is larger than Z_EROFS_PCLUSTER_MAX_DSIZE but the fragment is not the whole inode, it currently returns -EOPNOTSUPP because m_flags has the wrong EROFS_MAP_ENCODED flag set. It is not intended by design but should be rare, as it can only be reproduced by mkfs with `-Eall-fragments` in a specific case. Let's normalize fragment m_flags using the new EROFS_MAP_FRAGMENT. Reported-by: Axel Fontaine <axel@axelfontaine.com> Closes: https://github.com/erofs/erofs-utils/issues/23 Fixes: 7c3ca1838a78 ("erofs: restrict pcluster size limitations") Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20250711195826.3601157-1-hsiangkao@linux.alibaba.com Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-08-01erofs: clean up header parsing for ztailpacking and fragmentsGao Xiang1-25/+14
[ Upstream commit 540787d38b10dbc16a7d2bc2845752ab1605403a ] Simplify the logic in z_erofs_fill_inode_lazy() by combining the handling of ztailpacking and fragments, as they are mutually exclusive. Note that `h->h_clusterbits >> Z_EROFS_FRAGMENT_INODE_BIT` is handled above, so no need to duplicate the check. Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20250224123747.1387122-2-hsiangkao@linux.alibaba.com Stable-dep-of: b44686c8391b ("erofs: fix large fragment handling") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-08-01erofs: simplify tail inline pcluster handlingGao Xiang2-17/+12
[ Upstream commit b7710262d743aca112877d12abed61ce8a5d0d98 ] Use `z_idata_size != 0` to indicate that ztailpacking is enabled. `Z_EROFS_ADVISE_INLINE_PCLUSTER` cannot be ignored, as `h_idata_size` could be non-zero prior to erofs-utils 1.6 [1]. Additionally, merge `z_idataoff` and `z_fragmentoff` since these two features are mutually exclusive for a given inode. [1] https://git.kernel.org/xiang/erofs-utils/c/547bea3cb71a Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20250225114038.3259726-1-hsiangkao@linux.alibaba.com Stable-dep-of: b44686c8391b ("erofs: fix large fragment handling") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-08-01erofs: use Z_EROFS_LCLUSTER_TYPE_MAX to simplify switchesHongzhen Luo1-39/+24
[ Upstream commit 3b7781aeaefb627d4e07c1af9be923f9e8047d8b ] There's no need to enumerate each type. No logic changes. Signed-off-by: Hongzhen Luo <hongzhen@linux.alibaba.com> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Reviewed-by: Chao Yu <chao@kernel.org> Link: https://lore.kernel.org/r/20250210032923.3382136-1-hongzhen@linux.alibaba.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Stable-dep-of: b44686c8391b ("erofs: fix large fragment handling") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-08-01erofs: refine z_erofs_get_extent_compressedlen()Gao Xiang1-20/+16
[ Upstream commit 8f9530aeeb4f756bdfa70510b40e5d28ea3c742e ] - Set `compressedblks = 1` directly for non-bigpcluster cases. This simplifies the logic a bit since lcluster sizes larger than one block are unsupported and the details remain unclear. - For Z_EROFS_LCLUSTER_TYPE_PLAIN pclusters, avoid assuming `compressedblks = 1` by default. Instead, check if Z_EROFS_ADVISE_BIG_PCLUSTER_2 is set. It basically has no impact to existing valid images, but it's useful to find the gap to prepare for large PLAIN pclusters. Link: https://lore.kernel.org/r/20250123090109.973463-1-hsiangkao@linux.alibaba.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Stable-dep-of: b44686c8391b ("erofs: fix large fragment handling") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-08-01erofs: simplify z_erofs_load_compact_lcluster()Gao Xiang1-53/+36
[ Upstream commit 2a810ea79cd7a6d5f134ea69ca2ba726e600cbc4 ] - Get rid of unpack_compacted_index() and fold it into z_erofs_load_compact_lcluster(); - Avoid a goto. Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20250114034429.431408-1-hsiangkao@linux.alibaba.com Stable-dep-of: b44686c8391b ("erofs: fix large fragment handling") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-17erofs: fix rare pcluster memory leak after unmountingGao Xiang1-3/+4
commit b10a1e5643e505c367c7e16aa6d8a9a0dc07354b upstream. There may still exist some pcluster with valid reference counts during unmounting. Instead of introducing another synchronization primitive, just try again as unmounting is relatively rare. This approach is similar to z_erofs_cache_invalidate_folio(). It was also reported by syzbot as a UAF due to commit f5ad9f9a603f ("erofs: free pclusters if no cached folio is attached"): BUG: KASAN: slab-use-after-free in do_raw_spin_trylock+0x72/0x1f0 kernel/locking/spinlock_debug.c:123 .. queued_spin_trylock include/asm-generic/qspinlock.h:92 [inline] do_raw_spin_trylock+0x72/0x1f0 kernel/locking/spinlock_debug.c:123 __raw_spin_trylock include/linux/spinlock_api_smp.h:89 [inline] _raw_spin_trylock+0x20/0x80 kernel/locking/spinlock.c:138 spin_trylock include/linux/spinlock.h:361 [inline] z_erofs_put_pcluster fs/erofs/zdata.c:959 [inline] z_erofs_decompress_pcluster fs/erofs/zdata.c:1403 [inline] z_erofs_decompress_queue+0x3798/0x3ef0 fs/erofs/zdata.c:1425 z_erofs_decompressqueue_work+0x99/0xe0 fs/erofs/zdata.c:1437 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa68/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> However, it seems a long outstanding memory leak. Fix it now. Fixes: f5ad9f9a603f ("erofs: free pclusters if no cached folio is attached") Reported-by: syzbot+7ff87b095e7ca0c5ac39@syzkaller.appspotmail.com Closes: https://lore.kernel.org/r/674c1235.050a0220.ad585.0032.GAE@google.com Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20241203072821.1885740-1-hsiangkao@linux.alibaba.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-17erofs: fix to add missing tracepoint in erofs_readahead()Chao Yu1-0/+3
[ Upstream commit d53238b614e01266a3d36b417b60a502e0698504 ] Commit 771c994ea51f ("erofs: convert all uncompressed cases to iomap") converts to use iomap interface, it removed trace_erofs_readahead() tracepoint in the meantime, let's add it back. Fixes: 771c994ea51f ("erofs: convert all uncompressed cases to iomap") Signed-off-by: Chao Yu <chao@kernel.org> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20250707084832.2725677-1-chao@kernel.org Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-17erofs: refine readahead tracepointGao Xiang2-4/+3
[ Upstream commit 4eb56b0761e75034dd35067a81da4c280c178262 ] - trace_erofs_readpages => trace_erofs_readahead; - Rename a redundant statement `nrpages = readahead_count(rac);`; - Move the tracepoint to the beginning of z_erofs_readahead(). Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Reviewed-by: Hongbo Li <lihongbo22@huawei.com> Link: https://lore.kernel.org/r/20250514120820.2739288-1-hsiangkao@linux.alibaba.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Stable-dep-of: d53238b614e0 ("erofs: fix to add missing tracepoint in erofs_readahead()") Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-17erofs: tidy up zdata.cGao Xiang1-68/+43
[ Upstream commit 6f435e94a19ad25b372bc61443afd0839b8a521c ] All small code style adjustments, no logic changes: - z_erofs_decompress_frontend => z_erofs_frontend; - z_erofs_decompress_backend => z_erofs_backend; - Use Z_EROFS_DEFINE_FRONTEND() to replace DECOMPRESS_FRONTEND_INIT(); - `nr_folios` should be `nrpages` in z_erofs_readahead(); - Refine in-line comments. Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20250114034429.431408-3-hsiangkao@linux.alibaba.com Stable-dep-of: d53238b614e0 ("erofs: fix to add missing tracepoint in erofs_readahead()") Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-17erofs: get rid of `z_erofs_next_pcluster_t`Gao Xiang1-51/+29
[ Upstream commit 5514d8478b8ef3f0ba1b77beaa65f05c12825143 ] It was originally intended for tagged pointer reservation. Now all encoded data can be represented uniformally with `struct z_erofs_pcluster` as described in commit bf1aa03980f4 ("erofs: sunset `struct erofs_workgroup`"), let's drop it too. Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20250114034429.431408-2-hsiangkao@linux.alibaba.com Stable-dep-of: d53238b614e0 ("erofs: fix to add missing tracepoint in erofs_readahead()") Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-17erofs: free pclusters if no cached folio is attachedChunhai Guo1-19/+38
[ Upstream commit f5ad9f9a603f829d11ca31a0a4049e16091e8c13 ] Once a pcluster is fully decompressed and there are no attached cached folios, its corresponding `struct z_erofs_pcluster` will be freed. This will significantly reduce the frequency of calls to erofs_shrink_scan() and the memory allocated for `struct z_erofs_pcluster`. The tables below show approximately a 96% reduction in the calls to erofs_shrink_scan() and in the memory allocated for `struct z_erofs_pcluster` after applying this patch. The results were obtained by performing a test to copy a 4.1GB partition on ARM64 Android devices running the 6.6 kernel with an 8-core CPU and 12GB of memory. 1. The reduction in calls to erofs_shrink_scan(): +-----------------+-----------+----------+---------+ | | w/o patch | w/ patch | diff | +-----------------+-----------+----------+---------+ | Average (times) | 11390 | 390 | -96.57% | +-----------------+-----------+----------+---------+ 2. The reduction in memory released by erofs_shrink_scan(): +-----------------+-----------+----------+---------+ | | w/o patch | w/ patch | diff | +-----------------+-----------+----------+---------+ | Average (Byte) | 133612656 | 4434552 | -96.68% | +-----------------+-----------+----------+---------+ Signed-off-by: Chunhai Guo <guochunhai@vivo.com> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20241112043235.546164-1-guochunhai@vivo.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Stable-dep-of: d53238b614e0 ("erofs: fix to add missing tracepoint in erofs_readahead()") Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-17erofs: address D-cache aliasingGao Xiang5-19/+21
commit 27917e8194f91dffd8b4825350c63cb68e98ce58 upstream. Flush the D-cache before unlocking folios for compressed inodes, as they are dirtied during decompression. Avoid calling flush_dcache_folio() on every CPU write, since it's more like playing whack-a-mole without real benefit. It has no impact on x86 and arm64/risc-v: on x86, flush_dcache_folio() is a no-op, and on arm64/risc-v, PG_dcache_clean (PG_arch_1) is clear for new page cache folios. However, certain ARM boards are affected, as reported. Fixes: 3883a79abd02 ("staging: erofs: introduce VLE decompression support") Closes: https://lore.kernel.org/r/c1e51e16-6cc6-49d0-a63e-4e9ff6c4dd53@pengutronix.de Closes: https://lore.kernel.org/r/38d43fae-1182-4155-9c5b-ffc7382d9917@siemens.com Tested-by: Jan Kiszka <jan.kiszka@siemens.com> Tested-by: Stefan Kerkmann <s.kerkmann@pengutronix.de> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20250709034614.2780117-2-hsiangkao@linux.alibaba.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-17erofs: fix to add missing tracepoint in erofs_read_folio()Chao Yu1-0/+2
commit 99f7619a77a0a2e3e2bcae676d0f301769167754 upstream. Commit 771c994ea51f ("erofs: convert all uncompressed cases to iomap") converts to use iomap interface, it removed trace_erofs_readpage() tracepoint in the meantime, let's add it back. Fixes: 771c994ea51f ("erofs: convert all uncompressed cases to iomap") Signed-off-by: Chao Yu <chao@kernel.org> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20250708111942.3120926-1-chao@kernel.org Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-10add a string-to-qstr constructorAl Viro1-1/+1
[ Upstream commit c1feab95e0b2e9fce7e4f4b2739baf40d84543af ] Quite a few places want to build a struct qstr by given string; it would be convenient to have a primitive doing that, rather than open-coding it via QSTR_INIT(). The closest approximation was in bcachefs, but that expands to initializer list - {.len = strlen(string), .name = string}. It would be more useful to have it as compound literal - (struct qstr){.len = strlen(string), .name = string}. Unlike initializer list it's a valid expression. What's more, it's a valid lvalue - it's an equivalent of anonymous local variable with such initializer, so the things like path->dentry = d_alloc_pseudo(mnt->mnt_sb, &QSTR(name)); are valid. It can also be used as initializer, with identical effect - struct qstr x = (struct qstr){.name = s, .len = strlen(s)}; is equivalent to struct qstr anon_variable = {.name = s, .len = strlen(s)}; struct qstr x = anon_variable; // anon_variable is never used after that point and any even remotely sane compiler will manage to collapse that into struct qstr x = {.name = s, .len = strlen(s)}; What compound literals can't be used for is initialization of global variables, but those are covered by QSTR_INIT(). This commit lifts definition(s) of QSTR() into linux/dcache.h, converts it to compound literal (all bcachefs users are fine with that) and converts assorted open-coded instances to using that. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Stable-dep-of: cbe4134ea4bc ("fs: export anon_inode_make_secure_inode() and fix secretmem LSM bypass") Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19erofs: avoid using multiple devices with different typeSheng Yong1-1/+4
[ Upstream commit 9748f2f54f66743ac77275c34886a9f890e18409 ] For multiple devices, both primary and extra devices should be the same type. `erofs_init_device` has already guaranteed that if the primary is a file-backed device, extra devices should also be regular files. However, if the primary is a block device while the extra device is a file-backed device, `erofs_init_device` will get an ENOTBLK, which is not treated as an error in `erofs_fc_get_tree`, and that leads to an UAF: erofs_fc_get_tree get_tree_bdev_flags(erofs_fc_fill_super) erofs_read_superblock erofs_init_device // sbi->dif0 is not inited yet, // return -ENOTBLK deactivate_locked_super free(sbi) if (err is -ENOTBLK) sbi->dif0.file = filp_open() // sbi UAF So if -ENOTBLK is hitted in `erofs_init_device`, it means the primary device must be a block device, and the extra device is not a block device. The error can be converted to -EINVAL. Fixes: fb176750266a ("erofs: add file-backed mount support") Signed-off-by: Sheng Yong <shengyong1@xiaomi.com> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Reviewed-by: Hongbo Li <lihongbo22@huawei.com> Link: https://lore.kernel.org/r/20250515014837.3315886-1-shengyong1@xiaomi.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19erofs: fix file handle encoding for 64-bit NIDsHongbo Li1-8/+36
[ Upstream commit 510de8363f2c3d8e67fa9dfb2366e821382036e0 ] EROFS uses NID to indicate the on-disk inode offset, which can exceed 32 bits. However, the default encode_fh uses the ino32, thus it doesn't work if the image is larger than 128GiB. Let's introduce our own helpers to encode file handles. It's easy to reproduce: 1. prepare an erofs image with nid bigger than U32_MAX 2. mount -t erofs foo.img /mnt/erofs 3. set exportfs with configuration: /mnt/erofs *(rw,sync, no_root_squash) 4. mount -t nfs $IP:/mnt/erofs /mnt/nfs 5. md5sum /mnt/nfs/foo # foo is the file which nid bigger than U32_MAX. # you will get ESTALE error. In the case of overlayfs, the underlying filesystem's file handle is encoded in ovl_fb.fid, which is similar to NFS's case. If the NID of file is larger than U32_MAX, the overlay will get -ESTALE error when calls exportfs_decode_fh. Fixes: 3e917cc305c6 ("erofs: make filesystem exportable") Signed-off-by: Hongbo Li <lihongbo22@huawei.com> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20250507094015.14007-1-lihongbo22@huawei.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-29erofs: initialize decompression earlyGao Xiang3-28/+26
[ Upstream commit fe1e57d44d7f106df9048e815e4862cf63921220 ] - Rename erofs_init_managed_cache() to z_erofs_init_super(); - Move the initialization of managed_pslots into z_erofs_init_super() too; - Move z_erofs_init_super() and packed inode preparation upwards, before the root inode initialization. Therefore, the root directory can also be compressible. Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Acked-by: Chao Yu <chao@kernel.org> Link: https://lore.kernel.org/r/20250317054840.3483000-1-hsiangkao@linux.alibaba.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-18erofs: ensure the extra temporary copy is valid for shortened bvecsGao Xiang1-17/+14
[ Upstream commit 35076d2223c731f7be75af61e67f90807384d030 ] When compressed data deduplication is enabled, multiple logical extents may reference the same compressed physical cluster. The previous commit 94c43de73521 ("erofs: fix wrong primary bvec selection on deduplicated extents") already avoids using shortened bvecs. However, in such cases, the extra temporary buffers also need to be preserved for later use in z_erofs_fill_other_copies() to to prevent data corruption. IOWs, extra temporary buffers have to be retained not only due to varying start relative offsets (`pageofs_out`, as indicated by `pcl->multibases`) but also because of shortened bvecs. android.hardware.graphics.composer@2.1.so : 270696 bytes 0: 0.. 204185 | 204185 : 628019200.. 628084736 | 65536 -> 1: 204185.. 225536 | 21351 : 544063488.. 544129024 | 65536 2: 225536.. 270696 | 45160 : 0.. 0 | 0 com.android.vndk.v28.apex : 93814897 bytes ... 364: 53869896..54095257 | 225361 : 543997952.. 544063488 | 65536 -> 365: 54095257..54309344 | 214087 : 544063488.. 544129024 | 65536 366: 54309344..54514557 | 205213 : 544129024.. 544194560 | 65536 ... Both 204185 and 54095257 have the same start relative offset of 3481, but the logical page 55 of `android.hardware.graphics.composer@2.1.so` ranges from 225280 to 229632, forming a shortened bvec [225280, 225536) that cannot be used for decompressing the range from 54095257 to 54309344 of `com.android.vndk.v28.apex`. Since `pcl->multibases` is already meaningless, just mark `be->keepxcpy` on demand for simplicity. Again, this issue can only lead to data corruption if `-Ededupe` is on. Fixes: 94c43de73521 ("erofs: fix wrong primary bvec selection on deduplicated extents") Reviewed-by: Hongbo Li <lihongbo22@huawei.com> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20250506101850.191506-1-hsiangkao@linux.alibaba.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-18fs/erofs/fileio: call erofs_onlinefolio_split() after bio_add_folio()Max Kellermann1-2/+2
commit bbfe756dc3062c1e934f06e5ba39c239aa953b92 upstream. If bio_add_folio() fails (because it is full), erofs_fileio_scan_folio() needs to submit the I/O request via erofs_fileio_rq_submit() and allocate a new I/O request with an empty `struct bio`. Then it retries the bio_add_folio() call. However, at this point, erofs_onlinefolio_split() has already been called which increments `folio->private`; the retry will call erofs_onlinefolio_split() again, but there will never be a matching erofs_onlinefolio_end() call. This leaves the folio locked forever and all waiters will be stuck in folio_wait_bit_common(). This bug has been added by commit ce63cb62d794 ("erofs: support unencoded inodes for fileio"), but was practically unreachable because there was room for 256 folios in the `struct bio` - until commit 9f74ae8c9ac9 ("erofs: shorten bvecs[] for file-backed mounts") which reduced the array capacity to 16 folios. It was now trivial to trigger the bug by manually invoking readahead from userspace, e.g.: posix_fadvise(fd, 0, st.st_size, POSIX_FADV_WILLNEED); This should be fixed by invoking erofs_onlinefolio_split() only after bio_add_folio() has succeeded. This is safe: asynchronous completions invoking erofs_onlinefolio_end() will not unlock the folio because erofs_fileio_scan_folio() is still holding a reference to be released by erofs_onlinefolio_end() at the end. Fixes: ce63cb62d794 ("erofs: support unencoded inodes for fileio") Fixes: 9f74ae8c9ac9 ("erofs: shorten bvecs[] for file-backed mounts") Cc: stable@vger.kernel.org Signed-off-by: Max Kellermann <max.kellermann@ionos.com> Reviewed-by: Gao Xiang <xiang@kernel.org> Tested-by: Hongbo Li <lihongbo22@huawei.com> Link: https://lore.kernel.org/r/20250428230933.3422273-1-max.kellermann@ionos.com Signed-off-by: Gao Xiang <xiang@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-20erofs: set error to bio if file-backed IO failsSheng Yong1-0/+2
[ Upstream commit 1595f15391b81815e4ef91c339991913d556c1b6 ] If a file-backed IO fails before submitting the bio to the lower filesystem, an error is returned, but the bio->bi_status is not marked as an error. However, the error information should be passed to the end_io handler. Otherwise, the IO request will be treated as successful. Fixes: 283213718f5d ("erofs: support compressed inodes for fileio") Signed-off-by: Sheng Yong <shengyong1@xiaomi.com> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20250408122351.2104507-1-shengyong1@xiaomi.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08erofs: fix potential return value overflow of z_erofs_shrink_scan()Gao Xiang1-2/+1
[ Upstream commit db902986dee453bfb5835cbc8efa67154ab34caf ] z_erofs_shrink_scan() could return small numbers due to the mistyped `freed`. Although I don't think it has any visible impact. Fixes: 3883a79abd02 ("staging: erofs: introduce VLE decompression support") Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20250114040058.459981-1-hsiangkao@linux.alibaba.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08erofs: sunset `struct erofs_workgroup`Gao Xiang2-77/+60
[ Upstream commit bf1aa03980f4eb1599b866ccd2c4ac577ef56a8a ] `struct erofs_workgroup` was introduced to provide a unique header for all physically indexed objects. However, after big pclusters and shared pclusters are implemented upstream, it seems that all EROFS encoded data (which requires transformation) can be represented with `struct z_erofs_pcluster` directly. Move all members into `struct z_erofs_pcluster` for simplicity. Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20241021035323.3280682-3-hsiangkao@linux.alibaba.com Stable-dep-of: db902986dee4 ("erofs: fix potential return value overflow of z_erofs_shrink_scan()") Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08erofs: move erofs_workgroup operations into zdata.cGao Xiang3-112/+105
[ Upstream commit 9c91f959626e6d9f460b8906e27c37fca1b6456a ] Move related helpers into zdata.c as an intermediate step of getting rid of `struct erofs_workgroup`, and rename: erofs_workgroup_put => z_erofs_put_pcluster erofs_workgroup_get => z_erofs_get_pcluster erofs_try_to_release_workgroup => erofs_try_to_release_pcluster erofs_shrink_workstation => z_erofs_shrink_scan Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20241021035323.3280682-2-hsiangkao@linux.alibaba.com Stable-dep-of: db902986dee4 ("erofs: fix potential return value overflow of z_erofs_shrink_scan()") Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08erofs: get rid of erofs_{find,insert}_workgroupGao Xiang3-63/+30
[ Upstream commit b091e8ed24b7965953147a389bac1dc7c3e8a11c ] Just fold them into the only two callers since they are simple enough. Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20241021035323.3280682-1-hsiangkao@linux.alibaba.com Stable-dep-of: db902986dee4 ("erofs: fix potential return value overflow of z_erofs_shrink_scan()") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-27erofs: use buffered I/O for file-backed mounts by defaultGao Xiang3-10/+21
[ Upstream commit 6422cde1b0d5a31b206b263417c1c2b3c80fe82c ] For many use cases (e.g. container images are just fetched from remote), performance will be impacted if underlay page cache is up-to-date but direct i/o flushes dirty pages first. Instead, let's use buffered I/O by default to keep in sync with loop devices and add a (re)mount option to explicitly give a try to use direct I/O if supported by the underlying files. The container startup time is improved as below: [workload] docker.io/library/workpress:latest unpack 1st run non-1st runs EROFS snapshotter buffered I/O file 4.586404265s 0.308s 0.198s EROFS snapshotter direct I/O file 4.581742849s 2.238s 0.222s EROFS snapshotter loop 4.596023152s 0.346s 0.201s Overlayfs snapshotter 5.382851037s 0.206s 0.214s Fixes: fb176750266a ("erofs: add file-backed mount support") Cc: Derek McGowan <derek@mcg.dev> Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20241212134336.2059899-1-hsiangkao@linux.alibaba.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-27erofs: reference `struct erofs_device_info` for erofs_map_devGao Xiang4-23/+15
[ Upstream commit f8d920a402aec3482931cb5f1539ed438740fc49 ] Record `m_sb` and `m_dif` to replace `m_fscache`, `m_daxdev`, `m_fp` and `m_dax_part_off` in order to simplify the codebase. Note that `m_bdev` is still left since it can be assigned from `sb->s_bdev` directly. Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20241212235401.2857246-1-hsiangkao@linux.alibaba.com Stable-dep-of: 6422cde1b0d5 ("erofs: use buffered I/O for file-backed mounts by default") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-27erofs: use `struct erofs_device_info` for the primary deviceGao Xiang4-31/+22
[ Upstream commit 7b00af2c5414dc01e0718deef7ead81102867636 ] Instead of just listing each one directly in `struct erofs_sb_info` except that we still use `sb->s_bdev` for the primary block device. Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20241216125310.930933-2-hsiangkao@linux.alibaba.com Stable-dep-of: 6422cde1b0d5 ("erofs: use buffered I/O for file-backed mounts by default") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-27erofs: add erofs_sb_free() helperGao Xiang1-17/+19
[ Upstream commit e2de3c1bf6a0c99b089bd706a62da8f988918858 ] Unify the common parts of erofs_fc_free() and erofs_kill_sb() as erofs_sb_free(). Thus, fput() in erofs_fc_get_tree() is no longer needed, too. Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20241212133504.2047178-1-hsiangkao@linux.alibaba.com Stable-dep-of: 6422cde1b0d5 ("erofs: use buffered I/O for file-backed mounts by default") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-27erofs: fix PSI memstall accountingGao Xiang1-2/+2
[ Upstream commit 1a2180f6859c73c674809f9f82e36c94084682ba ] Max Kellermann recently reported psi_group_cpu.tasks[NR_MEMSTALL] is incorrect in the 6.11.9 kernel. The root cause appears to be that, since the problematic commit, bio can be NULL, causing psi_memstall_leave() to be skipped in z_erofs_submit_queue(). Reported-by: Max Kellermann <max.kellermann@ionos.com> Closes: https://lore.kernel.org/r/CAKPOu+8tvSowiJADW2RuKyofL_CSkm_SuyZA7ME5vMLWmL6pqw@mail.gmail.com Fixes: 9e2f9d34dd12 ("erofs: handle overlapped pclusters out of crafted images properly") Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20241127085236.3538334-1-hsiangkao@linux.alibaba.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05erofs: handle NONHEAD !delta[1] lclusters gracefullyGao Xiang1-8/+9
[ Upstream commit 0bc8061ffc733a0a246b8689b2d32a3e9204f43c ] syzbot reported a WARNING in iomap_iter_done: iomap_fiemap+0x73b/0x9b0 fs/iomap/fiemap.c:80 ioctl_fiemap fs/ioctl.c:220 [inline] Generally, NONHEAD lclusters won't have delta[1]==0, except for crafted images and filesystems created by pre-1.0 mkfs versions. Previously, it would immediately bail out if delta[1]==0, which led to inadequate decompressed lengths (thus FIEMAP is impacted). Treat it as delta[1]=1 to work around these legacy mkfs versions. `lclusterbits > 14` is illegal for compact indexes, error out too. Reported-by: syzbot+6c0b301317aa0156f9eb@syzkaller.appspotmail.com Closes: https://lore.kernel.org/r/67373c0c.050a0220.2a2fcc.0079.GAE@google.com Tested-by: syzbot+6c0b301317aa0156f9eb@syzkaller.appspotmail.com Fixes: d95ae5e25326 ("erofs: add support for the full decompressed length") Fixes: 001b8ccd0650 ("erofs: fix compact 4B support for 16k block size") Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20241115173651.3339514-1-hsiangkao@linux.alibaba.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05erofs: fix blksize < PAGE_SIZE for file-backed mountsHongzhen Luo1-1/+5
[ Upstream commit bae0854160939a64a092516ff1b2f221402b843b ] Adjust sb->s_blocksize{,_bits} directly for file-backed mounts when the fs block size is smaller than PAGE_SIZE. Previously, EROFS used sb_set_blocksize(), which caused a panic if bdev-backed mounts is not used. Fixes: fb176750266a ("erofs: add file-backed mount support") Signed-off-by: Hongzhen Luo <hongzhen@linux.alibaba.com> Link: https://lore.kernel.org/r/20241015103836.3757438-1-hongzhen@linux.alibaba.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05erofs: fix file-backed mounts over FUSEGao Xiang2-4/+7
[ Upstream commit 3a23787ca8756920d65fda39f41353a4be1d1642 ] syzbot reported a null-ptr-deref in fuse_read_args_fill: fuse_read_folio+0xb0/0x100 fs/fuse/file.c:905 filemap_read_folio+0xc6/0x2a0 mm/filemap.c:2367 do_read_cache_folio+0x263/0x5c0 mm/filemap.c:3825 read_mapping_folio include/linux/pagemap.h:1011 [inline] erofs_bread+0x34d/0x7e0 fs/erofs/data.c:41 erofs_read_superblock fs/erofs/super.c:281 [inline] erofs_fc_fill_super+0x2b9/0x2500 fs/erofs/super.c:625 Unlike most filesystems, some network filesystems and FUSE need unavoidable valid `file` pointers for their read I/Os [1]. Anyway, those use cases need to be supported too. [1] https://docs.kernel.org/filesystems/vfs.html Reported-by: syzbot+0b1279812c46e48bb0c1@syzkaller.appspotmail.com Closes: https://lore.kernel.org/r/6727bbdf.050a0220.3c8d68.0a7e.GAE@google.com Fixes: fb176750266a ("erofs: add file-backed mount support") Tested-by: syzbot+0b1279812c46e48bb0c1@syzkaller.appspotmail.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20241114234905.1873723-1-hsiangkao@linux.alibaba.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-10-21erofs: use get_tree_bdev_flags() to avoid misleading messagesGao Xiang1-1/+3
Users can pass in an arbitrary source path for the proper type of a mount then without "Can't lookup blockdev" error message. Reported-by: Allison Karlitskaya <allison.karlitskaya@redhat.com> Closes: https://lore.kernel.org/r/CAOYeF9VQ8jKVmpy5Zy9DNhO6xmWSKMB-DO8yvBB0XvBE7=3Ugg@mail.gmail.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20241009033151.2334888-2-hsiangkao@linux.alibaba.com Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-10-14Merge tag 'erofs-for-6.12-rc4-fixes' of ↵Linus Torvalds3-43/+31
git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs Pull erofs fixes from Gao Xiang: "The main one fixes a syzbot issue due to the invalid inode type out of file-backed mounts. The others are minor cleanups without actual logic changes. Summary: - Make sure only regular inodes can be used for file-backed mounts - Two minor codebase cleanups" * tag 'erofs-for-6.12-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs: erofs: get rid of kaddr in `struct z_erofs_maprecorder` erofs: get rid of z_erofs_try_to_claim_pcluster() erofs: ensure regular inodes for file-backed mounts
2024-10-11erofs: get rid of kaddr in `struct z_erofs_maprecorder`Gao Xiang1-20/+12
`kaddr` becomes useless after switching to metabuf. Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20241010235830.1535616-1-hsiangkao@linux.alibaba.com
2024-10-11erofs: get rid of z_erofs_try_to_claim_pcluster()Gao Xiang1-20/+9
Just fold it into the caller for simplicity. Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20241010090420.405871-1-hsiangkao@linux.alibaba.com
2024-10-11erofs: ensure regular inodes for file-backed mountsGao Xiang1-3/+10
Only regular inodes are allowed for file-backed mounts, not directories (as seen in the original syzbot case) or special inodes. Also ensure that .read_folio() is implemented on the underlying fs for the primary device. Fixes: fb176750266a ("erofs: add file-backed mount support") Reported-by: syzbot+001306cd9c92ce0df23f@syzkaller.appspotmail.com Closes: https://lore.kernel.org/r/00000000000011bdde0622498ee3@google.com Tested-by: syzbot+001306cd9c92ce0df23f@syzkaller.appspotmail.com Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20240917130803.32418-1-hsiangkao@linux.alibaba.com